Early- and Middle-Term Surgical Outcomes in Patients with Heterotaxy Syndrome

Objectives: Heterotaxy syndrome is a recognized risk factor for surgical cardiac interventions. We evaluated the early- and middle-term results of a surgical intervention for patients with heterotaxy syndrome. Methods: A total of 42 patients with heterotaxy syndrome were enrolled (September 2008 to March 2015). Left and right atrial isomerism were identified in 26% (11 out of 42) and 74% of patients (31 out of 42), respectively. The median age of the patients at the time of surgery was 6.8 months (range: 5 days to 22.3 years). Biventricular repair was completed in 3 patients with left atrial isomerism. Seventeen out of 39 patients who were scheduled for single ventricular repair completed a modified Fontan procedure. Results: The hospital mortality rate was 4.7% (2 out of 42). Another 5 deaths occurred in the remaining survivors following hospital discharge with a follow-up duration of 45.8 ± 23.6 months (range: 13-111 months). The 1-year and 5-year survival rates were 88.1% (37/42) and 83.3% (35/42), respectively. Univariate analysis and multivariate analysis identified pulmonary venous obstruction and atrioventricular valve replacement as additional risk factors for mortality. Conclusions: Right ventricular bypass surgery remains the preferred palliative procedure for patients with heterotaxy syndrome. Based on the current results, the early- and middle-term outcomes are satisfactory.

Coronary collateral growth and its therapeutic application to coronary artery disease

There is a tremendous body of data concerning the coronary collateral circulation in both experimental animals and humans. The functional importance of a well-developed coronary collateral circulation has now been documented. The paradigm regarding the principal stimulus for coronary collateral growth has shifted from myocardial ischemia to increased shear stress at the site of pre-existing collateral arterioles. Numerous experimental and clinical studies have contributed to elucidation of the mechanisms of coronary collateral growth. Stimulation of coronary collateral growth is an alternative therapeutic approach to patients with intractable angina pectoris who are not indicated for percutaneous coronary intervention and/or coronary artery bypass grafting. Pharmacological and mechanical modulations accelerating coronary collateral growth have been challenged. Because it is conceivable that a well-developed coronary collateral circulation attenuates myocardial ischemia upon exercise, further research addressing coronary collateral growth is needed in both experimental models of myocardial ischemia and human coronary artery disease.